Do not store invalid response

[vbartusevicius]

Description

When the max_duration option is used in the PSR18 client, it may result in a partial/corrupted body that is stored without any checks for its validity. Then in DefaultUnleashRepository:parseFeatures, the JsonException is thrown and is bubbled up for the end-user. Additionally, the Stale cache is polluted.

More on the error: symfony/symfony#52490

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

• Unit tests
• Spec Tests
• Integration tests / Manual Tests

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[RikudouSage]

Looks good, thank you for your contribution!